Detachable grip for increasing leverage of tool handles



DETACHABLE GRIP FOR INCREASING LEVERAGE OF TOOL HANDLES Filed Jan. 9,1952 I In;

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United States Patent f) DETACHABLE GRIP FQR INCREASING LEVEHAGEDFTUOIIHKNDLES Edward N. Keyes, Short Hills, N. J.

Application January 9, 1952, Serial No. 265,696

1 Claim. (Cl. 145-61) This invention relates to an auxiliary tool handlethat is detachably applied over the ordinary permanent handle of a screwdriver, or other rotary tool, to increase the torque that can be exertedwith the tool.

Various types of auxiliary tool handles have been proposed and it is anobject of this invention to provide an improved auxiliary handle whichcombines substantial increase in leverage with convenience inapplication and removal, and with simplicity and very low manufacturingcost.

In the preferred construction, the auxiliary handle of this invention isan integral unit without any moving parts and with a hub portion thathas a recess for receiving the tool handle. The recess has straightsides and a transverse cross-section that corresponds to that of thetool handle.

The tool handle may fit tightly with a slight wedging action when fullyinserted into the recess of the auxiliary handle, but it does not fittightly enough to prevent it from being pulled out of the recess by handwhen the auxiliary handle is to be removed from the tool.

With this invention a set of hand tools can have the usual smalldiameter handles, and the resulting convenience in storing in a toolchest; and any one of them can be used to apply greater torque, thanwould otherwise be possible, by applying the auxiliary handle of thisinvention over the permanent handle of the particular tool selected foruse.

Other objects, features and advantages of the invention will appear orbe pointed out as the description proceeds.

In the drawing, forming a part hereof, in which like referencecharacters indicate corresponding parts in all the views,

Figure 1 is a side elevation of a screw driver equipped with anauxiliary handle made in accordance with this invention; and

Figure 2 is a sectional view taken on line 2-2 of Figure 1.

Figure 1 shows a screw driver having a working element with its lowerend shaped to fit into a screw slot, and a shank 11 at its upper endextending into a handle 12. The shank 11 is commonly made with a squarecross section in order to prevent it from turning in the handle 12. Thesocket in the handle, which holds the shank, has a cross sectioncorresponding to that of the shank and fits tightly so that the shankand handle are permanently connected to one another. Screw driverscommonly have a ferrule 14 at the lower end of the handle to prevent anyspreading of the handle, when the handle is made of wood, and forornamental purposes with handles that do not need to be reinforcedagainst spreading.

The screw driver shown in the drawing is merely representative of rotaryhand tools, and it will be understood that the handle 12 may be thepermanent handle of any hand tool which is operated by rotating about anaxis which extends lengthwise of the handle. The material, of which thehandle 12 is made, may be wood, metal, plastics, or any other substancesuitable for the purpose.

The handles of tools which must be rotated about their 2,725,086 we 2a 1Wheel extendsv from one, side of. the wheel. 17; and preferably from thelower side only so as to leave the upper side of the wheel unobstructed.This makes it possible to obtain a firmer grip on the wheel 17 whenturning it with one hand.

The hub 18 has an annular face 22 at the end of the hub remote from thewheel, as best shown in Figure 1. There is a recess 24 opening throughthe end face 22, and this recess preferably extends throughout most ofthe longitudinal length of the recess 24 to an upper end wall 25 at thetop of the recess 24.

The recess 24 has a transverse cross section with flutes which extendinto the grooves between the flutes 15 of the handle. In order to havethe auxiliary handle fit tools of different sizes, there is a shoulder23 intermediate the upper and lower ends of the recess 24, and the crosssection of the recess above the shoulder 23 is smaller than below theshoulder. The recess 24 below the shoulder 23, is of the same transversecross section as the handle 12, and the upper end of the handle abutsagainst the annular surface provided by the shoulder. The upper portionof the recess, above the shoulder, fits a handle of smaller size. Otherembodiments of the invention can have different cross sections, ofnon-circular contour, that engage the fluted handle 12 without fittinginto all of the contours of the handle.

It is a feature of the invention, however, that the recess 24 is ofnon-circular, transverse cross section; and that the auxiliary handle isheld against rotation, with respect to the tool, by having thenon-circular recess 24 fit noncircular portions of the handle 12 so asto force the permanent handle 12 to rotate with the auxiliary handle 17.

The sides of the recess 24 are preferably straight, at least throughoutthe greater portion of their length; and in any event, the sides of therecess 24 extend in directions substantially the same as the sides ofthe tool handle with which the auxiliary handle is to be used.

Toward the upper end of recess 24 the side walls of the recess arepreferably made so that they converge slightly and grip the upper end ofthe handle 12 with enough wedge action to hold the handle 12 in therecess 24. As previously explained, this wedging action is light and theauxiliary handle can always be pulled off by hand.

The preferred embodiment of the invention has been illustrated anddescribed, but changes and modifications can be made without departingfrom the invention as described in the appended claim.

What is claimed is:

A hand grip element for use with a tool which has a working element witha shank extending into and rigidly connected with a tool handle whichhas a section of substantially uniform diameter with flutes in itsoutside surface for facilitating the gripping of the handle, said gripelement including a wheel having a top face with a broad convex surfacefor comfortable contact against the palm of the hand of a person usingthe grip element to exert both the axial and torque forces required foroperation to be performed by the tool, the wheel having a roundedperpiheral portion and a bottom face with which the peripheral portionmerges and under which the fingers of the hand extend when the wheel isfirmly gripped with its top face against the palm of the hand, and a hubfor the one-p iececop s truct ion with thewheel, but

wheel rigidly connected with the remainder of the wheel and extendingdownwardly for a substantial distance below said bottomface at asubstantial distance inward from the peripheral portion of the wheel,said hub havinga lower end face with a recess opening therein andextending up- 5 ward to a location above the bottom face of the wheeland the recess having side walls parallel to one another and fluted forat least the lower portion of their length and said recess having across section that fits the cross section of the handle of the tool withwhich the element is intended to 10 be used.

References Cited in the file of this patent UNITED STATES PATENTS445,451 Miller Jan.27, 1891 15 4 Chesson June 27, 1899 Jacobs May 18,1909 Probst Mar. 7, 1911 Barnes June 21, 1921 Booth Sept. 20, 1921Peterson Oct. 5, 1926 Schneider Dec. 31, 1929 Fratz Dec. 2, 1952 FOREIGNPATENTS France Sept. 14, 1926

